Phase stability and electronic structure of Si2Sb2Te5 phase-change material

Abstract

On the basis of an ab initio computational study, the present work provide a full understanding on the atomic arrangements, phase stability as well as electronic structure of Si2Sb2Te5, a newly synthesized phase-change material. The results show that Si2Sb2Te5 tends to decompose into Si1Sb2Te4 or Si1Sb4Te7 or Sb2Te3, therefore, a nano-composite containing Si1Sb2Te4, Si1Sb4Te7 and Sb2Te3 may be self-generated from Si2Sb2Te5. Hence Si2Sb2Te5 based nano-composite is the real structure when Si2Sb2Te5 is used in electronic memory applications. The present results agree well with the recent experimental work. (C) 2010 Elsevier Ltd. All rights reserved.